1. Field of the Invention
This invention relates to a connector having press-connecting terminals mounted in a connector housing, and more particularly to an improved connector housing, each of said pressing connecting terminals having a press-connecting blade to which an electric wire with a sheath is press-connected electrically.
2. Related Art
In automobiles incorporating electronic devices, not to mention various kinds of electronic equipment, connectors have been extensively used for connecting wires together or for connecting an electronic equipment. Generally, such a connector has terminals mounted in a housing, each of the terminals having an electric wire connected thereto. There is known the type of connector in which the connection between the wire and the terminal is made not by soldering or crimping but by press-connecting.
One example of conventional press-connecting terminal, as well as a conventional connector, will now be described with reference to FIGS. 8 to 11. Referring first to the press-connecting terminal T, an upwardly-open U-shaped slot 1 is formed in a plate portion, formed by stamping and raising part of a bottom portion 6 of the press-connecting terminal T, thereby forming a press-connecting blade 2, as shown in FIGS. 8 and 9. An electric wire 3 shown at the upper side in the drawings is press-fitted into the press-connecting blade 2 as indicated by an arrow. Upon press-fitting of the wire 3, an edge of the press-connecting blade 2 cuts a sheath 4 of the wire 3, thereby electrically connecting a conductor 5 of the wire 3 to the press-connecting blade 2.
However, the press-connecting portion defined by the U-shaped slot 1 is weak against an external pulling force acting on the wire 3, and therefore insulation barrel portions 8 (hereinafter referred merely to "barrel portions") disposed rearwardly of the press-connecting blade 2 are formed by bending portions of the terminal plate, and these barrel portions are pressed around the wire 3 to bear the external pulling force of the wire 3, thereby retaining the press-connected portion, as shown in FIG. 9.
When the wire 3 or a wire harness comprising such wires 3 tied together is to be installed in an automobile or the like, a large external pulling force acts on the wire 3, and unless this external force is borne, an imperfect contact is liable to develop in the press-connected portion. Therefore, the press-connecting terminal T has been mounted in a connector housing 12 (hereinafter referred merely to "housing") as shown in FIGS. 10 and 11.
As best shown in FIG. 11, a wire receiving hole 9 having an open bottom is formed adjacent to a rear end of a terminal receiving chamber 13 of the housing 12, that is, at a right side (indicated by arrow A in FIG. 10) from which the press-connecting terminal T is inserted. Opposed plate-like resilient pieces 15 project respectively from the front rear edges of this bottom opening in a cantilever manner, and these resilient pieces 15 constitute bottom portions of the wire receiving hole 9.
A wire holder member 10 shogun above the housing 12 has a row of wire holder projections 16 formed on a lower surface thereof, the wire holder projections 16 corresponding respectively to the wire receiving holes 9. The wire holder member 10 also has retaining pieces 18 having respective retaining holes 19 in which retaining pawls 17 formed respectively at the opposite sides or ends of the housing 12 are engageable, respectively.
A plurality of interconnected press-connecting terminals T are separated from one another, and are received in the housing 12. The wire 13 is fitted in each terminal receiving chamber 13 as shown in FIG. 11, and the wire holder member 10 is attached to the housing from the upper side to cause each wire holder projection 16 to urge the corresponding wire 3 downwardly, so that the wire 3 is bulged into the wire receiving hole 9 to form a curved or bent wire portion 20.
As a result, the resilient pieces 15 are displaced downwardly by the bent wire portion 20 of the wire 3, and urge the bent wire portion 20 upwardly against the wire holder projection 16 by their resilient force. Namely, the resilient pieces 15 and the wire holder member 10 hold the wire therebetween to bear an external pulling force acting on the wire 3, thus performing a strain relief function.
The above-mentioned housing structure is disclosed in Japanese Utility Model Unexamined Publication No. 4-15161.
In the above housing construction, the wire holder member 10 separate from the housing 12 is needed for bearing an external pulling force acting on the wire 3. Therefore, the number of the component parts is increased, and the number of man-hours to assemble the component parts is increased because the wire holder member 10 must be attached. These contributes to an increased cost.
Since the wire holder member 10 is mounted on the housing 12, the outer size of the housing 12 after such mounting is increased, and besides this is a barrier to a multi-stage construction.
Furthermore, depending on the outer diameter of the wire 3, the wire holder member 10 can not often be attached. When the wire 3 is too small in diameter, the strain relief function is not achieved at all, and thus this construction lacks in versatility.